Disability can linger years after mild wartime brain injuries

Military service members who sustain concussions in combat may experience worsening symptoms for several years after their injuries, particularly if they have psychiatric problems, a small U.S. study suggests.

About one in five U.S. service members deployed in the wars in Iraq and Afghanistan suffered a head injury, researchers note in JAMA Neurology. Most of them endured mild uncomplicated brain injuries or concussions.

Previous research has linked these injuries to multiple mental health problems but hasn’t provided a clear picture of exactly what influences the severity or duration of symptoms.

For the current study, researchers compared health outcomes over five years for 50 active-duty service members with combat experience who sustained combat concussions and 44 who didn’t suffer brain injuries.

With concussions, combat veterans were more likely to have post-traumatic stress disorder, severe depression, anxiety and sleep difficulties.

The study also found that after a concussion, symptoms got worse from one to five years following the injury. This suggests one common assumption guiding concussion treatment - that patients tend to stabilize within a year of their injuries - might not always be right, said lead study author Christine Mac Donald of the University of Washington School of Medicine in Seattle.

“In short, there is nothing ‘mild’ about these injuries,” Mac Donald said by email.

“There is evolution not resolution of symptoms that occur years after these exposures and we in the medical research community should not only be working hard to develop therapies that can be administered acutely after injury but also, and this is a bit of a paradigm shift, focus on developing therapies and treatment strategies targeted to the chronic phase of injury as well,” Mac Donald added.

All of the service members with concussions had been evacuated from Afghanistan to a medical center in Germany for treatment between 2008 and 2013. Study participants without concussions had received treatment for noncombat health problems like gastrointestinal tract issues or dermatitis.

At one and five years after joining the study, 36 of the 50 concussion patients, or 72 percent, had declining scores on an evaluation that measures overall disability.

In addition, satisfaction with life, disability, and the severity of neurobehavioral and psychiatric symptoms were worse with patients who had concussions than participants who didn’t have brain injuries.

However, people with and without concussions performed similarly on cognitive function tests after five years.

Some of the factors that might increase the odds of worse outcomes after five years include the brain injury diagnosis as well as pre-injury intelligence, motor strength, verbal fluency and neurobehavioral symptoms like headache, insomnia, fatigue and depression, the study also found.

While the study is small, and more research is needed in larger groups of concussion patients in the military and other populations, the authors conclude that psychiatric symptoms rather than cognitive deficits may be driving long-term symptoms.

The military has a comprehensive approach to treating battlefield concussions, which is one of the key advances from the wars in Iraq and Afghanistan, noted Dr. Jack Tsao, coauthor of an accompanying editorial and a researcher at the University of Tennessee Health Science Center and the Memphis Veterans Affairs Medical Center.

“Focusing on mild traumatic brain injuries, in the period immediately following concussion or mild traumatic brain injury, we know that injured service members typically make an excellent recovery and are able to return to full duty,” Tsao said by email.

“The focus of treatment immediately following injury is rest and education about what to expect during recovery, similar to what is recommended for a sports- or accident-related concussion,” Tsao added. “If symptoms persist and become diagnosed as persistent post-concussive syndrome or if new mental health conditions emerge and are diagnosed, additional treatment targeted towards the symptoms is warranted.”

SOURCE: JAMA Neurology, online May 1, 2017.